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+;;; srfi-26.scm --- specializing parameters without currying.
+
+;; Copyright (C) 2002, 2006, 2010 Free Software Foundation, Inc.
+;;
+;; This library is free software; you can redistribute it and/or
+;; modify it under the terms of the GNU Lesser General Public
+;; License as published by the Free Software Foundation; either
+;; version 3 of the License, or (at your option) any later version.
+;;
+;; This library is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+;; Lesser General Public License for more details.
+;;
+;; You should have received a copy of the GNU Lesser General Public
+;; License along with this library; if not, write to the Free Software
+;; Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+
+(define-module (srfi srfi-26)
+ :export (cut cute))
+
+(cond-expand-provide (current-module) '(srfi-26))
+
+(define-syntax cut
+ (lambda (stx)
+ (syntax-case stx ()
+ ((cut slot0 slot1+ ...)
+ (let loop ((slots #'(slot0 slot1+ ...))
+ (params '())
+ (args '()))
+ (if (null? slots)
+ #`(lambda #,(reverse params) #,(reverse args))
+ (let ((s (car slots))
+ (rest (cdr slots)))
+ (with-syntax (((var) (generate-temporaries '(var))))
+ (syntax-case s (<> <...>)
+ (<>
+ (loop rest (cons #'var params) (cons #'var args)))
+ (<...>
+ (if (pair? rest)
+ (error "<...> not on the end of cut expression"))
+ #`(lambda #,(append (reverse params) #'var)
+ (apply #,@(reverse (cons #'var args)))))
+ (else
+ (loop rest params (cons s args))))))))))))
+
+(define-syntax cute
+ (lambda (stx)
+ (syntax-case stx ()
+ ((cute slots ...)
+ (let loop ((slots #'(slots ...))
+ (bindings '())
+ (arguments '()))
+ (define (process-hole)
+ (loop (cdr slots) bindings (cons (car slots) arguments)))
+ (if (null? slots)
+ #`(let #,bindings
+ (cut #,@(reverse arguments)))
+ (syntax-case (car slots) (<> <...>)
+ (<> (process-hole))
+ (<...> (process-hole))
+ (expr
+ (with-syntax (((t) (generate-temporaries '(t))))
+ (loop (cdr slots)
+ (cons #'(t expr) bindings)
+ (cons #'t arguments)))))))))))